**11. The role of Capgras syndrome in violence**

Acting on delusions is a crucial clinical issue. There is a positive relationship between delusions and serious violent acts. Although the pathway from delusions to violent outcomes is not direct, the risk is greatly increased when symptoms are acute, especially at the time of initial presentation and if not treated [19]. And the risk also can be changed according to the etiology of delusions. There is a requirement to be concerned about the patient's tendency for violence and to evaluate for it thoroughly in Capgras delusion [45]. In patients with CS of an organic nature, violence may be associated with few or no affective manifestations (e.g., hostility, aggression, and auditory hallucinations), and may not be associated with paranoid elements [7]. Delusional symptoms in CS such as persecutory thoughts, threatcontrol symptoms, command auditory and/or visual hallucinations, and hallucinations of threatening content have all demonstrated to be significant predictors of violence act and aggressive behaviour [28]. If the patients are married, divorced, or separated, the most frequent doubles are the spouse. If the patients are single, the most frequent doubles are the siblings [19]. It should be noted that healthcare professionals may become the objects of delusional misidentification [42]. Because the double is usually assumed to have malicious, the CS could be characterized by hostility toward misidentified objects, and, later, it can lead to physical harm to others [19]. The assault associated with CS, the tendency to violence, cannot be attributed purely to the delusion's existence. Other factors are presumably to affect the possibility of violent act. A significantly higher tendency for interpersonal violence are men disclosed among male subjects, average age at 40 years old, with a history of aggressive behaviour and substance abuse; social withdrawal prior to the violent act is common, and the violence is usually well planned [19, 21, 22]. Persecutory paranoid motivations have been implicated as a key factor in acts of violence toward family members who constitute the majority of victims in CS [28]. Physical violence was expressed by 58.2% of patients with CS and 62.5% of patients with CS engaged in acts of interpersonal violence toward their close family members and caregivers [21, 22]. Mothers and spouses were the most frequently attacked group of relatives, respectively. Also, it was found that 1 of 10 Capgras patients attempted homicide [21, 22]. Most of the perpetrators were males suffering from mental disorders without organic association. A higher incidence of self-harm and suicide attempts, which is about 1 in 10 of patients with CS, was detected among females even in patients with psychiatric disorders and in patients with neurodegenerative disorders [21, 22]. Although in the usual cases, the misidentified object is a person, hence justifying the title of delusional identification of people, the CS is not restricted to person misidentification but can also involve other living or lifeless objects [7, 19]. Physical violence against objects was also common, such as setting fire to one else's estate [21, 22].
